The present invention relates to an actuator, and more particularly, to a plurality of actuators controlled independently of one another, an actuator system including a plurality of actuators, and a connector for connecting a plurality of actuators.
A typical actuator system, such as one used in a vehicle air conditioner, includes a plurality of actuators, each having a driving portion. The actuator system drives the driving portions of the actuators independently of one another. In such an actuator system, an address is set for each actuator. Further, the actuators are connected to one another and to a master controller through a local area network (LAN). The LAN decreases the number of wires in the actuator system.
Each actuator includes a connector connected to a signal line and power supply lines. Japanese Patent No. 2679209 describes an example of such a connector, which includes a plurality of terminals (contacts) and a cover. In this connector, a ribbon-shaped harness (flat cable) is sandwiched between the cover and a housing to connect the terminals to the signal line and power supply lines (wires) of the ribbon-shaped harness. More specifically, each terminal is bifurcated so as to define a slit between the bifurcated portions. The bifurcated portions penetrate through an insulation film, which covers the signal line and the power supply lines, when sandwiching the ribbon-shaped harness. This connects the signal and power supply lines to the terminal. Accordingly, the actuator, which includes such a connector, is easily connected to the ribbon-shaped harness.
When a plurality of actuators are connected to one another with such connectors and a single ribbon-shaped harness, each actuator is connected in parallel by the signal line. Due to the parallel connection, an address must be set beforehand for each actuator. Accordingly, there is a need for a circuit to set the ID numbers (e.g., a pattern corresponding to the addresses of the actuators must be configured on a substrate incorporated each of the actuators). This increases the cost of each actuator, which, in turn, increases the cost of an actuator system including a plurality of actuators.
When the above connector and single ribbon-shaped harness are not used and a plurality of actuators are daisy chain connected with one another, a different ID number does not have to be set for each actuator (the actuators may be identical to each other). If, however, the actuators are daisy chain connected, a plurality of signal lines become necessary to connect the actuators to one another. In an actuator system including a plurality of actuators, this increases the number of components and causes the connection of the actuators to become complicated. Thus, the configuration of an actuator system including a plurality of actuators is expensive.